WELCOME TO RIVER DAVES PLACE

New project followed me home...'73 Spectra

redone76

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Sold my Chaparral deck boat last year cause it wasn't being used much. Started to get the itch for another boat so I hopped on the internet....

Found this 1973 Spectra 18 jet boat project on OfferUp and headed out last Tuesday to take a look.

Guy got in over his head mechanical wise when he realized the timing cover on the 455 Olds engine was leaking water into the oil. He's had the intake and valve covers off for almost 2 years now.

Other than it not being covered very well and the engine issue that's about all i can see wrong with it. It's original gelcoat, stringers and floor are fantastic. Fiberglass tank has been upgraded to a 38 gallon IMCO belly tank. Berekely 12JC looks solid except for the bowl paint. It's had a place diverter added to it. Original seats are in so so condition. No big rips or tears. Wood looks great as well. Original shag carpet is gone but the guy had made new marine carpet templates before he tossed the shag.

So I gave her a deep scrub this weekend and started my to do list...
Change oil and do a compression test to see if this 455 is healthy
Yank the engine to replace the timing cover and get a look at the bottom end
Yank the floor to give the hull a good cleaning and install the carpet while the floor panels are out
Get a closer eye on the pump input side
Install a bilge blower
Repaint the jet bowl
Sand and oil the teak swim steps
Deep clean and condition the interior
Polish and wax the gelcoat
Go through the trailer...gotta find some era correct wheels. Thinking mags or turbines
Anyone know where I can get a windshield made? I found the original mounting brackets under a seat

I'll keep updating the thread as I go. Plan to get my 10 year old son involved this summer to teach him some skills and keep him off the tablet

Any tips, tricks or suggestions are more than welcome...
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redone76

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Looks like a nice find. Install engine oil drain with hose when you have the engine out..
Funny you say that cause it has one...problem was i couldn't figure out how to get the hose out the bilge plug hole without putting an upward bend in the hose and the oil wouldn't drain out! I ended up just using my fluid extractor down the hose to suck the old oil out.
 

redone76

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Being an Olds, if the motor needs to be rebuilt call Mondellos and get all of their products to help the oiling issues. My first boat had a 455 that I used their products on and never had an issue in 18 years.
Thanks for the heads up! I've been studying up on the 455 oiling issues. Is there any way to tell if my engine has had work done for that?
 

CommanderLee

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Thanks for the heads up! I've been studying up on the 455 oiling issues. Is there any way to tell if my engine has had work done for that?
The cam bearings will have a tiny hole in them for oiling. In the main bearing oil galleys there would be restrictors. Reduces them from about the size of a pencil to the lead inside of it. With this and a 10 quart pan it should live a good long time. I always ran VR1 20W50 in mine as well. This combo worked very well for me for 18 trouble free years.
 

Jay Dub

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Sold my Chaparral deck boat last year cause it wasn't being used much. Started to get the itch for another boat so I hopped on the internet....

Found this 1973 Spectra 18 jet boat project on OfferUp and headed out last Tuesday to take a look.

Guy got in over his head mechanical wise when he realized the timing cover on the 455 Olds engine was leaking water into the oil. He's had the intake and valve covers off for almost 2 years now.

Other than it not being covered very well and the engine issue that's about all i can see wrong with it. It's original gelcoat, stringers and floor are fantastic. Fiberglass tank has been upgraded to a 38 gallon IMCO belly tank. Berekely 12JC looks solid except for the bowl paint. It's had a place diverter added to it. Original seats are in so so condition. No big rips or tears. Wood looks great as well. Original shag carpet is gone but the guy had made new marine carpet templates before he tossed the shag.

So I gave her a deep scrub this weekend and started my to do list...
Change oil and do a compression test to see if this 455 is healthy
Yank the engine to replace the timing cover and get a look at the bottom end
Yank the floor to give the hull a good cleaning and install the carpet while the floor panels are out
Get a closer eye on the pump input side
Install a bilge blower
Repaint the jet bowl
Sand and oil the teak swim steps
Deep clean and condition the interior
Polish and wax the gelcoat
Go through the trailer...gotta find some era correct wheels. Thinking mags or turbines
Anyone know where I can get a windshield made? I found the original mounting brackets under a seat

I'll keep updating the thread as I go. Plan to get my 10 year old son involved this summer to teach him some skills and keep him off the tablet

Any tips, tricks or suggestions are more than welcome...
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looks like a fun project, enjoy
 

coolchange

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Always liked those and the little Hallets too. Check the bottom while the motors out.
 

redone76

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The cam bearings will have a tiny hole in them for oiling. In the main bearing oil galleys there would be restrictors. Reduces them from about the size of a pencil to the lead inside of it. With this and a 10 quart pan it should live a good long time. I always ran VR1 20W50 in mine as well. This combo worked very well for me for 18 trouble free years.
Thanks for the detailed info. It has a 10 quart pan on it already. I'll report back what i find after i crack the bottom end open
 

JUSTWANNARACE

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On the 455 I believe there is some kind of stuffer that needs to be put in under the intake for cooling or something like that. I'm not an olds guy but @n2otoofast4u could fill you in. I know he just did all this not to long ago on one of his.
 

redone76

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On the 455 I believe there is some kind of stuffer that needs to be put in under the intake for cooling or something like that. I'm not an olds guy but @n2otoofast4u could fill you in. I know he just did all this not to long ago on one of his.
Cool! I look forward to seeing what he has to say. I did see Mondellos makes a windage tray that keeps the hot oil off the bottom of the intake
 

redone76

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Got some fresh oil in her and she has 35 psi while cranking. Had my son hop in and we had fun learning about compression testing and how it works.

Cold engine with the intake off these were our numbers
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Squirt some oil in the low cylinders and 5 is the only one that slightly increased. #8 spit the oil out the intake side so that tells me something is up with that valve.

Regardless the engine is getting pulled so I'll pop the heads off and see what's what.
 

Sleek-Jet

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Mondellos actually wrote a book on modifying the Olds big blocks. I'm sure you can still pick it up on Amazon, it's worth getting as a reference if nothing else.

If the engine in the boat is the same Hardin Marine engine that the boat came with, then it has all of the good parts. The good blocks, crank, K or Ka heads and stuff like that. These started out as 390 hp Toronado crate engines.

As was mentioned, if not already done a few easy mods makes the Olds a reliable engine for a weekend fun boat. If you desire to try and win river drag races with it you'll need to start spending $$$ if you want to stay with team Rocket.
 
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redone76

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Mondellos actually wrote a book on modifying the Olds big blocks. I'm sure you can still pick it up on Amazon, it's worth getting as a reference if nothing else.

If the engine in the boat is the same Hardin Marine engine that the boat came with, then it has all of the good parts. The good blocks, crank, K or Ka heads and stuff like that. These started out as 390 hp Toronado crate engines.

As was mentioned, if not already done a few easy mods makes the Olds a reliable engine for a weekend fun boat. If you desire to try and win river drag races with it you'll need to start spending $$$ if you want to stay with team Rocket.
So the story goes that I bought it from the second owner. His uncle being the first. He's not sure about the engines history but supposedly it was never touched. It does have a 10 quart pan. It has KA heads and an Edelbrock Olds 455 performer intake. What can I look for inside the block? I believe it's all original Hardin marine
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I have zero plans of racing this thing! Haha! Just want a nice reliable unique cruiser.
 

Sleek-Jet

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I used to know all of that backward and forwards, but it has been 20 years since I was neck deep in Olds stuff. The fact the Ka heads are still there means that if someone swapped in a smog motor from the late 70's at least they kept the heads.

There is a web page called Oldsmobile FAQ or something along those lines, Google is your friend there. Between the content on that site and Mondello's book you can answer most, if not all, of the questions you have.
 

redone76

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I used to know all of that backward and forwards, but it has been 20 years since I was neck deep in Olds stuff. The fact the Ka heads are still there means that if someone swapped in a smog motor from the late 70's at least they kept the heads.

There is a web page called Oldsmobile FAQ or something along those lines, Google is your friend there. Between the content on that site and Mondello's book you can answer most, if not all, of the questions you have.
Great info! I'll start googling! Thanks again!!
 

redone76

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Cleaned up the wheels and gave them a few coats of clear. New lug nuts and valve stems. Ready for some rubber
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Got the rust off the steering wheel and gave it a polish. Oiled the wood as well
Before...

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After...
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Polished up some other stuff...
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Sanded and oiled up the teak swim steps
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Now I gotta get this engine out and focus on that! Stop messing with the little crap
 
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redone76

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The Spectra project got put on hold for a month or so while I wrapped up a few other little projects around the house. So to get back into it I removed all the interior and gave it a deep clean and conditioning. It'll work for now until I decide what I want to do with the interior.
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Pulled up the floor which was actually pretty easy with it being in sections screwed to the stringers. Gonna reseal and carpet with black marine carpet.
Gave the hull and stringers a good cleaning/inspection. I was happy with how it looked and felt. Nice and solid for being 50 years old
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redone76

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Yanked the 455 and got it on a stand for tear down...
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Cracked open the engine and it was pretty clean inside. Intake valves had some rust and the timing cover was toast. Dropped the heads off for a rebuild. Tore down the rest of the engine and did some measuring. It looks really good and it's all stock inside. I plan to refresh it with a quick hone job, new bearings and rings.
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redone76

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Honed and cleaned up the cylinders. All oil passages cleaned and inspected. New rings and bearings installed. I also went with a mild Comp marine cam and Cloyes double roller timing setup. Just waiting on the call for the heads to be ready...
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redone76

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Realized I haven't updated this thread for a bit....

Got the rebuilt heads back and reinstalled with adjustable rocker arms
Assembled the rest of the engine and started hanging the mounting brackets and accessories
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n2otoofast4u

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Does that intake have the exhaust blocked where the factory carb used the “heat tube” for a choke?
 

redone76

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While running we noticed the tach and amp meter wasn't working. Drug her home and ordered a nice simple set of black Faria gauges. Changed out the bulbs for yellow LED's and installed the new gauges. Then I started laying out the carpet for the floor
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redone76

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After I was satisfied with the carpet I started bolting back in the cleaned-up OG interior. Replaced all the tired shag carpet with fresh black carpet on the seats and engine housing. Battery mount and battery installed. Jet-A-Vator set and bolted where i wanted. Cleaned up and reoiled the OG teak swim steps and got them bolted back on
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redone76

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Took her to Puddingstone for her maiden voyage. She's a floater! Putted around for a bit getting used to her and then we did some left-hand laps for about an hour. Engine and pump worked great, and I'm beyond stoked. Even hit an honest 50mph on the GPS before running out of space on the lake. Holidays and life got in the way, but I need to get back on the water with her ASAP. I did find some time to repair and install the original bimini top it came with
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n2otoofast4u

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You’re good to go then.

When I rebuilt mine, I tried to reuse the factory manifold because it was low enough to keep my arrestor under the hatch. Well, after multiple ways of blocking the factory hole, plugging the head, etc. I could never get it to stop boiling the fuel once it was shut off. Finally gave up and cut a hole in the hatch, went to an aulm intake manifold with a 650 brawler with the choke gutted and haven’t looked back. I have 1000s of miles on my 455. I run the impeller size up so it will never turn big RPM and it cruises at almost 30 at 2800rpm. @JUSTWANNARACE had tagged me earlier and I didn’t see it, but he has 100s of miles in the passenger seat of mine and we always laugh about how I literally just built a river cruiser.
 

redone76

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You’re good to go then.

When I rebuilt mine, I tried to reuse the factory manifold because it was low enough to keep my arrestor under the hatch. Well, after multiple ways of blocking the factory hole, plugging the head, etc. I could never get it to stop boiling the fuel once it was shut off. Finally gave up and cut a hole in the hatch, went to an aulm intake manifold with a 650 brawler with the choke gutted and haven’t looked back. I have 1000s of miles on my 455. I run the impeller size up so it will never turn big RPM and it cruises at almost 30 at 2800rpm. @JUSTWANNARACE had tagged me earlier and I didn’t see it, but he has 100s of miles in the passenger seat of mine and we always laugh about how I literally just built a river cruiser.
Good to know! My engine had an Edelbrock aluminum manifold with the exhaust crossover already blocked off on both sides. Good idea on running the impeller a size up to keep RPM down. I need to put more seat time on it in a bigger body of water and see what she does
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mash on it

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AA American Turbine impeller, is ever so slightly larger than an A2 from Berkeley. (Thanks Tom)
Also 30 @2800 rpm or so.
My big girl tops out at a whopping 57 up river, @4900 R's (mild 454)

Dan'l

Sounds good, BTW
 

redone76

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Thank you, sir! I'm looking forward to getting her on the river soon
 
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